50 AGE OF THE DOMESTIC ANIMALS. 



the age of old horses is by means of the " knots " in the tail. 

 Tliese knots are little, prominent eminences on either side of the 

 base of the tail, formed by the transverse process of the coccygeal 

 bones. The processes can be felt in young horses, and become 

 especially prominent after the emaciation of a severe illness, but 

 in this case they are rounded and are apparently continuous with 

 the other tissues, while in old horses, due to absorption in the 

 bone itself, they become more distinct, and seem to stand out 

 in the muscles and softer structures of the tail. 



The knots are felt distinctly at the base of the tail when 

 the horse has attained the age of thirteen years. In two years 

 later, when they have become more prominent, they have be- 

 hind them a distinct little depression two or three lines in width. 

 At sixteen a second pair of knots are found, which, like the firsts 

 in about two years, have behind them a distinct depression, and 

 so on, every three years, a new pair of knots furnish an approxi- 

 mately accurate indication of the age of the animal. 



The teeth, however, are by far the most important wit- 

 nesses of the age of the horse. The examination of these^ 

 which includes the incisors, the tusks, and the molars, shows 

 (a) if the incisive arch is composed of teeth of the first or second 

 dentition, or of both ; (h) if there is a normal number of them ; 

 (c) the situation, length, breadth, and the angle v/hich they 

 have in the maxillary bones ; (d) if the tables of the teeth touch 

 each other, or if one overreaches the other, which somewhat 

 modifies the leveling of the table; (e) the color and substances 

 on the face of the teeth; (/) if they have been subjected to 

 fraudulent handling. 



In the incisors we study the form and details of the table, 

 the direction and length of the tooth, and the condition of the 

 corner tooth. In the tusks we note the amount of use to which 

 the teeth have been subjected, their direction and their length. 

 In the molars we look for the number and the dentition to 

 which they belong, the condition of their grinding surface, their 

 length and direction and the integrity of their substance, and 

 that of the gums which surround them. 



